I don't understand the meaning of the English sentence correctly.

It's a triple denial, so it's hard to understand even if it's translated into Japanese, but if you change the expression a little, you'll say, "I won't add phpdocs that only contain information already in the signature."

The purpose is to keep the header doc principle (although Japanese projects are often not followed) that information that can be found in signatures (method names, argument names, argument types) should not be written in the header doc.

^{This post was edited based on @Ooper's Comment and posted as Community Wiki.This post was edited based on @Ooper's Comment and posted as Community Wiki.}